In general, a line blind valve is located on a boundary of a pipe for a hydraulic test, and is configured to block and open fluid flow of a pipe. Furthermore, the line blind valve is installed in pipes for different types of fluids so as to prevent the fluids from being introduced into each other or to prevent the fluids from being mixed with each other. Usually, the line blind valve is utilized in pipes of a vessel or plant.
As shown in FIG. 1, in a line blind valve according to the related art, in order to block a pipeline, an upper cover 20 of a valve body 10 provided between pipes is opened, and a double disk 30 is inserted into the valve body 10. Thereafter, the upper cover 20 is closed. In order to open the pipeline, the upper cover is opened, and the double disk 30 is separated from the valve body 10. Thereafter, the upper cover 20 is closed.
It is problematic in that the line blind valve according to the related art requires a dedicated device since it is hard to lift weight of the double disk 30 by human power, thereby increasing time required to insert or separate the double disk 30.
Furthermore, in the line blind valve according to the related art, since dead space is formed between the double disk 30 and the valve body 10, it is problematic in that different types of fluids are mixed or are gathered in the dead space, thereby contaminating the fluids.
Furthermore, in the line blind valve according to the related art, when the double disk 30 is separated from the valve body 10 so as to open the pipeline, since pressure generated by fluid flow is applied to the entire valve body 10, it is complicated to design the valve body 10 to be sealed. Thus, it is problematic in that weight of the valve body 10 is increased.
Accordingly, a line blind valve for solving the above-mentioned problems is required.